The problem we are trying to resolve is that today we don't have a transparent way of mapping from one telemetry framework data sets to other telemetry framework data sets. There is a multitude of write plugins that normalize data from one set to the other, however they are implementation specific (per framework/protocol they implement). We'd like to leverage a common description language to establish a methodology for normalizing data sets between frameworks, i.e. a way of describing mapping from one data set to another. Then use generic write plugins that can parse the appropriate schema, do the real mapping on the fly and submit the information to the relevant end point (unfortunately there still might need to be specific write plugins/utilities for authentication with the relevant end point).

To help work through the schema proposals, we will work through a use case to normalize data from the internal collectd format to the ceilometer format.

Ceilometer use case

Ceilometer provides the possibility to submit samples via the REST API to allow users to send custom samples into this service. The samples that can be sent to Telemetry are not limited to the actual existing meters. There is a possibility to provide data for any new, customer defined counter by filling out all the required fields of the POST request. If the sample corresponds to an existing meter, then the fields like meter-type and meter name should be matched accordingly.

Issues:

Proposal 1 is too high level and doesn't get into the internals of what meters get mapped to what and what units should be associated with the meters/events - in essence it doesn't improve on what's there today for overlapping meters. However is good for new meters.